var LAYER_FADE_DURATION = 200; // ms

function showLayer($layer, center, with_shade)
{
  center = typeof(center) != 'undefined' ? center : true;
  //with_shade = typeof(with_shade) != 'undefined' ? with_shade : true;
  if ($('.layer:visible').length) $('.layer:visible').hide();
  if ($('.layer_mini:visible').length) $('.layer_mini:visible').hide();
  var layerTop = $(window).scrollTop() + ($(window).height() / 2 - $layer.height() / 2);
  if (layerTop < 0) layerTop = 0;
  var layerLeft = $(window).scrollLeft() + ($(window).width() / 2 - $layer.width() / 2);
  if (layerLeft < 0) layerLeft = 0;
  //$('#shade').css('height', $(document).height() + 'px');
  //if (with_shade) $('#shade').fadeIn(LAYER_FADE_DURATION);
  if ($.browser.msie)
    $layer.show();
  else
    $layer.fadeIn(LAYER_FADE_DURATION, function() {
      $layer.css('filter', '');
    });
  if (center)
  {
    $layer.css('top', layerTop + 'px');
    $layer.css('left', layerLeft + 'px');
  }
}


function hideLayer($layer)
{
  //$('#shade').fadeOut(LAYER_FADE_DURATION);
  if ($.browser.msie)
    $layer.hide();
  else
    $layer.fadeOut(LAYER_FADE_DURATION);
}